In the LDS Church handbook Teachings of the Presidents of the Church: Joseph Smith, there was a paragraph on how Joseph Smith began his conference talks. Since they were often outdoors, it was often difficult for everyone to hear. Thus, the following paragraph, found on page 493 of the said manual:
"When the Prophet spoke outdoors, he often began his talks by asking the Saints to pray for the wind or rain to be calmed until he got through speaking. At a conference held in Nauvoo on April 8, 1843, the Prophet began an address by saying: 'I have three requests to make of the congregation: The first is, that all who have faith will exercise it and pray the Lord to calm the wind; for as it blows now, I cannot speak long without seriously injuring my health; the next is that I may have your prayers that the Lord will strengthen my lungs, so that I may be able to make you all hear; and the third is, that you will pray for the Holy Ghost to rest upon me, so as to enable me to declare those things that are true.' ” (History of the Church, 5:339; from a discourse given by Joseph Smith on Apr. 8, 1843, in Nauvoo, Illinois; reported by Willard Richards and William Clayton.)
For us, I would summarize as follows:
1. Pray for the proper teaching environment.
2. Make sure that everyone can hear you clearly. If this means you have to yell, then pray for the strength to yell.
3. Only teach the truth as manifest by the Holy Ghost.
